1. Field of the Invention
This invention relates to an optical interconnection system, and in particular to an interconnection system for hybrid optical motherboards.
2. Related Art
A hybrid optical motherboard is a motherboard including optical interconnections and other optical components, and is, therefore, the optical equivalent of a printed circuit board (pcb). Electrical interconnections for the optical components are also provided on the motherboard as appropriate. One simple example of the flexibility of hybrid optical motherboard technology is shown in FIG. 13.
Optical connectors are required to interconnect the optical interconnections of a hybrid optical motherboard and other optical components (which may form part of another hybrid optical motherboard). Such an optical connector must accurately align with optical interconnections on the motherboard, and must mate with a complementary connector region of the motherboard.
It is known to use micromachined silicon V-grooves for alignment purposes in such connector/connector region combinations. Thus, European patent specification 331334 describes a connector made from two identical silicon substrates which are held in precision alignment using two metal guiding rods which are pressed against bevelled edges of the substrates, the bevelled edges being formed by cleaving or sawing each of the substrates along the centers of the pair of micromachined V-grooves. The disadvantage of such an arrangement is that it is only possible to form a maximum of two connector regions on any one component, the connector regions being on opposite edges of the component and utilizing the same pairs of V-grooves to form the alignment means for each region.
By analogy with the electrical interconnection of pcbs, it is readily apparent that applications exist where it would be advantageous to form several optical connector regions on one optical component. A hybrid optical motherboard is one such example.